Migrating from core.
Default date should be NULL, to avoid having the end user submit unintended value.
Correcting typo and setting NULL value.
Merge pull request #1553 from craigh/datepicker2

This PR was merged into zikula:1.3 branch.

Discussion
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Datepicker2

@shefik 's PR correctly rebased.

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| Refs tickets  |#1500
| License       | MIT
| Doc PR        | -

Commits
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bf0d311238369fbf9010becf56c8cecad684deb5 Migrating from core. shefik
a09a8d458f3913304abd05b8844eb4077d941e0d Default date should be NULL, to avoid having the end user submit unintended value. shefik
471092ae983b2692319c6e1fa9fcb41ea49d41b7 Correcting typo and setting NULL value. shefik