Increase code coverage

[enkogu]

Before:

--------------------------------------------|----------|----------|----------|----------|----------------|
File                                        |  % Stmts | % Branch |  % Funcs |  % Lines |Uncovered Lines |
--------------------------------------------|----------|----------|----------|----------|----------------|
 contracts/                                 |        0 |      100 |        0 |        0 |                |
  FallbackToWeiReceiver.sol                 |        0 |      100 |        0 |        0 |       16,20,21 |
 contracts/bases/                           |    74.73 |    70.59 |    74.47 |    75.27 |                |
  ExpenseBase.sol                           |    33.33 |      100 |       50 |    33.33 |... 52,53,57,58 |
  SplitterBase.sol                          |       80 |      100 |    72.73 |       80 |          49,57 |
  TableBase.sol                             |    85.71 |    68.75 |    82.14 |    86.15 |... 170,178,186 |
 contracts/ether/                           |       80 |      100 |    81.25 |    71.43 |                |
  WeiAbsoluteExpense.sol                    |      100 |      100 |      100 |      100 |                |
  WeiAbsoluteExpenseWithPeriod.sol          |      100 |      100 |      100 |      100 |                |
  WeiAbsoluteExpenseWithPeriodSliding.sol   |      100 |      100 |      100 |      100 |                |
  WeiExpense.sol                            |       75 |      100 |       75 |    66.67 |          33,34 |
  WeiRelativeExpense.sol                    |      100 |      100 |      100 |      100 |                |
  WeiRelativeExpenseWithPeriod.sol          |      100 |      100 |      100 |      100 |                |
  WeiRelativeExpenseWithPeriodSliding.sol   |      100 |      100 |        0 |      100 |                |
  WeiSplitter.sol                           |      100 |      100 |      100 |      100 |                |
  WeiTable.sol                              |    66.67 |      100 |    66.67 |       60 |          20,21 |
 contracts/examples/                        |       25 |       50 |    27.27 |       25 |                |
  DefaultMoneyflowScheme.sol                |       50 |       50 |    22.22 |       50 |             78 |
  DefaultMoneyflowSchemeWithUnpackers.sol   |        0 |      100 |       50 |        0 |          17,18 |
 contracts/examples/moneyflow/              |        0 |      100 |        0 |        0 |                |
  Roadmap.sol                               |        0 |      100 |        0 |        0 |... 14,15,16,17 |
 contracts/examples/weiTable/               |        0 |      100 |        0 |        0 |                |
  Budget.sol                                |        0 |      100 |        0 |        0 |... 119,120,121 |
  Roadmap.sol                               |        0 |      100 |        0 |        0 |... 27,29,30,31 |
 contracts/interfaces/                      |      100 |      100 |      100 |      100 |                |
  IDestination.sol                          |      100 |      100 |      100 |      100 |                |
  IReceiver.sol                             |      100 |      100 |      100 |      100 |                |
  ISplitter.sol                             |      100 |      100 |      100 |      100 |                |
  ITable.sol                                |      100 |      100 |      100 |      100 |                |
  ITokenReceiver.sol                        |      100 |      100 |      100 |      100 |                |
  IWeiReceiver.sol                          |      100 |      100 |      100 |      100 |                |
 contracts/libs/                            |    93.44 |    83.57 |    91.67 |    93.79 |                |
  ExpenseLib.sol                            |    91.92 |    77.78 |      100 |     93.1 |... 169,170,171 |
  SplitterLib.sol                           |    95.24 |       94 |    85.71 |    94.44 |... ,73,212,216 |
 contracts/tokens/                          |    94.12 |       50 |    88.24 |       92 |                |
  ERC20AbsoluteExpense.sol                  |      100 |      100 |      100 |      100 |                |
  ERC20AbsoluteExpenseWithPeriod.sol        |      100 |      100 |      100 |      100 |                |
  ERC20AbsoluteExpenseWithPeriodSliding.sol |      100 |      100 |      100 |      100 |                |
  ERC20Expense.sol                          |      100 |       50 |      100 |      100 |                |
  ERC20RelativeExpense.sol                  |      100 |      100 |      100 |      100 |                |
  ERC20RelativeExpenseWithPeriod.sol        |      100 |      100 |      100 |      100 |                |
  ERC20RelativeExpenseWithPeriodSliding.sol |      100 |      100 |        0 |      100 |                |
  ERC20Splitter.sol                         |      100 |       50 |      100 |      100 |                |
  ERC20Table.sol                            |       80 |       50 |       75 |       75 |          28,29 |
  ERC20Token.sol                            |      100 |      100 |      100 |      100 |                |
--------------------------------------------|----------|----------|----------|----------|----------------|
All files                                   |    77.42 |    79.67 |    68.22 |    67.33 |                |
--------------------------------------------|----------|----------|----------|----------|----------------|```