#98 Event and Era periods are limited

[roger lindberg]

There is a limitation in Timeline preventing users from entering very long periods (>1200 years) for Era's and Event's.

Sea also ticket #90 'Can't zoom wider than 1200 years'

Some users need to have longer Events and/or Eras and therefore the current limitaion is a problem.

[roger lindberg]

Suggested solution: Remove the limitation of period length entirely.

[roger lindberg]

This problem was solved in #90