Fixed multiple issues related to values with decimal points

[manish-in-java]

I had run into and fixed the following problems with the plugin:

1. Precision specified when initialising the plugin was not being used for typed values. For example, I could type 999.9999 with precision of 2;
2. Minimum value specified when initialising the plugin was not being used for typed values. For example, I could type 100 with a minimum value of 1000;
3. Maximum value specified when initialising the plugin was not being used for typed values. For example, I could type 100 with a maximum value of 99;
4. I could type a value with a decimal point even after initialising the plugin with int type;
5. Float values lost decimal point when using the up and down buttons. For example, if I initialised a control with the value 100.00, with a precision of 2, the value would become 99 on using the down button and 101 on using the up down, although the expected values would be 99.00 and 101.00 respectively.

Please review and merge if appropriate.